Earth excavating apparatus

ABSTRACT

An earth working apparatus which includes a self-powered vehicle having a pair of blade-supporting mounting arms pivotally supported on opposite sides thereof, and extending forwardly from the vehicle. A bulldozer blade is mounted on the forward ends of these arms in front of the vehicle, and has a sliding center ball brace assembly extending transversely across the rear side of the blade from one end thereof to the other, and spaced upwardly from the lower edge of the blade. A plurality of scarifier teeth are pivotally mounted in brackets secured along the backside of the blade below the ball brace assembly, and adjacent the lower side of the blade.

D United States Patent [1 1 [111 3,776,317 Royer Dec. 4, 1973 EARTH EXCAVATING APPARATUS Primary Examiner-Robert E. Pultrey Assistant ExaminerStephen C. Pellegrino [76] Inventor g gg g gg z, 33 Att0rney-Dunlap, Laney, Hessin and Dougherty [22] Filed: May 17, 1971 57 ABSTRACT 21 App]. No.: 143,828

An earth working apparatus which includes a selfpowered vehicle having a pair of blade-supporting [52] US. Cl. 172/777, 172/803 mounting arms pivotauy Supported on opposite Sides lllt. thereof, and extending from the vehicle. A Of Search bulldozer is mounted on the forward ends of 172/803 662; 37/141 T these arms in front of the vehicle, and has a sliding center ball brace assembly extending transversely [561 References C'ted across the rear side of the blade from one end thereof UNITED STATES PATENTS to the other, and spaced upwardly from the lower 3,395,764 8/1968 Wirt 172/803 ge f th bla A plurality of scarifier teeth are piv- 2,396,739 3/1946 McCauley... 172/777 otally mounted in brackets secured along the backside 2,700,833 2/1955 Small 172/777 of the blade below the ball brace assembly, and adjacent the lower side of the blade.

9 Claims, 4 Drawing Figures PATENTEDUEE 41m 3,776,317

INVENTOE CZADY LA @075? EARTH EXCAVATING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to earth working apparatus of the bulldozer type, and more particularly, relates to an assembly which includes a bulldozer scraper blade hav ing mounted on the rear side thereof a plurality of scarifier teeth.

2. Brief Description of the Prior Art The normal function of a bulldozer scraper blade of the type mounted forward of a continuous tracked tractor is to scrape away a layer of earth and push it ahead of the tractor as the tractor advances. It has heretofore been proposed to mount on the rear side of the bulldozer blade, a plurality of scarifier or ripper teeth which are free to pivot rearwardly and upwardly about a horizontal axis as the blade is pushed forward and into the ground by the advance of the tractor supporting the blade. The scarifier teeth then pivot downwardly to a vertically extending position, and are held in this position by positive stops, at such time as the tractor is reversed for the purpose of taking another bite in the earth with the bulldozer blade. This pivotal action of the scarifier teeth permits them to dig into the earth during the rearward movement of the tractor and loosen the earth so that it may be more easily removed on the next advance of the tractor when the bulldozer blade lowered for earth removal purposes.

As most bulldozers were heretofore constructed, no significant problem was encountered in mounting scari fier or ripper teeth on the rear side of the bulldozer blade, since this side of the blade offered a large expanse of anchoring metal extending substantially in a vertical plane so that adequate space was available for welding, or otherwise suitably securing, along this side of the blade, the brackets for pivotally supporting the sacrifier teeth. Recently, however, a new design of bulldozer blade-carrying tractor has been marketed by the Caterpillar Tractor Company, which design provides a sliding center ball brace assembly extending along the back side of the bulldozer blade from one end thereof to the other at a location spaced upwardly a short distance from the lower side of the blade. The mounting of the ball brace assembly at this location has been believed to prevent scarifier teeth from being pivotally mounted on the back of the bulldozer blade, since the space normally available for this purposehas been preempted by the inclusion of the sliding center ball brace assembly. It has been thought that an insufficient amount of metal remains available between transverse rods forming a part of the sliding center ball brace assembly and the lower side of the bulldozer blade to permit tooth supporting brackets of sufficient strength to withstand the forces of large magnitude to which such brackets are subjected when the scarifier teeth bite into hard or rocky terrain to be secured to the blade at this location. Because of these considerations, no construction has been heretofore devised by which the desirable scarifier teeth could be effectively mounted on the newer style of bulldozer of the type described.

BRIEF DESCRIPTION 'OF THE PRESENT INVENTION The present invention provides an earth working apparatus of the bulldozer type which includes, in combination, an elongated bulldozer blade having a sliding center ball brace assembly mounted adjacent the rear side of the blade, and further having a plurality of horizontally spaced scarifier teeth pivotally mounted on the back side of the blade near the lower edge thereof, with each of these teeth being independently pivotable about a horizontal axis. The bulldozer blade, sliding center ball brace assembly, and scarifier teeth thus present a compact arrangement in which the teeth are sturdily mounted on the back of the blade and function to rip and pulverize the earth during the reverse movement of a tractor upon which the assembly is mounted.

Broadly described, the present invention comprises an elongated bulldozer blade having a concave forward surface and having a rear side opposite said forward side; a sliding center ball brace assembly extending across the back side of the bulldozer blade in a horizontal direction and spaced upwardly from the lower side of the blade, the ball brace assembly including a pair of substantially horizontally aligned stabilizer rods each connectable at one end to the supporting arms of the tractor used to support the blade; and a plurality of scarifier teeth assemblies mounted on the backside of the bulldozer blade adjacent the lower side thereof and spaced horizontally along the bulldozer blade. Each scarifier tooth assembly includes a mounting bracket subassembly pivotally supporting the shank portion of a scarifier tooth for pivotation about a horizontal axis so that each scarifier tooth in each of the teeth assem blies is free to pivot through an are away from the bulldozer blade, but is arrested from pivotation in the opposite direction by a positive stop at a time when the respective tooth is in a vertically extending position.

An object of the present invention is to provide a compact earth working apparatus for mounting on a self-propelled vehicle, which apparatus includes an elongated bulldozer blade for scraping away a layer of earth, and a plurality of horizontally spaced, pivotally mounted scarifier teeth which can rip and pulverize the earth when the bulldozer blade is not in use.

Another object of the invention is to provide an arrangement for mounting a plurality of scarifier teeth on the backside of the bulldozer blade which is stabilized by means of a sliding center ball brace assembly extending along the back side of the blade.

An additional-object of the invention is to provide a bulldozer blade assembly which includes a sliding center ball brace which eliminates push arm bowing stresses during tilting of the bulldozer blade, and which also includes, in close proximity to the ball brace as sembly on the backside of the bulldozer blade, a plurality of horizontally spaced, pivotally mounted scarifier teeth.

Other objects and advantages of the invention will become apparent as the following detailed description of the invention is read in conjunction with the accompanying drawings which illustrate the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view illustrating the earth working apparatus of the invention as it appears when mounted upon a tracked, self-propelled vehicle.

FIG. 2 is a view partly in elevation, and partly in section, of one end portion of a bulldozer blade and the associated ball brace assembly and scarifier teeth, as the blade, ball brace assembly and scarifier teeth appear when viewed from the rear side of the blade.

FIG. 3 is a sectional view taken along 3-3 of FIG. 2.

FIG. 4 is a plan view of a portion of the structure depicted in FIG. 2, with a part of the bulldozer blade and a part of the mounting arm and ball brace assembly broken away for clarity of illustration.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION Referring initially to FIG. 1 of the drawings, shown therein is a continuous tracked, self-propelled vehicle 10. In accordance with conventional construction, the vehicle has pivotally mounted to the frame thereof a pair of supporting side arms 12. The arms 12 extend forwardly from the vehicle 10, and have mounted at their forward ends a bulldozer blade designated generally by reference numeral 14. As is typical of the construction of one blade of this type, the bulldozer blade 14 has a concavely shaped forward side 16 (See FIG. 3), and a comparatively monoplanar rear side 18 on the opposite side of the blade from the concave forward side. The blade 14, according to operation procedure well understood in the art, can be elevated and lowered by pivotation of the supporting arms 12, and can be tilted about a horizontal axis extending through the center thereof by means of push arms 20.

In accordance with a recent construction of bulldozer which has been marketed, a sliding center ball brace assembly designated generally by reference numeral 22 is mounted on the rear side 18 of the blade 14 adjacent the lower side thereof, and functions to eliminate bowing stresses imposed on the blade during digging operations in which the blade is tilted or canted with respect to the horizontal. The sliding center ball brace assembly 22 also distributes side loading to both the push arms equally, thus extending the life of these arms. The sliding center ball brace assembly 22 includes a pair of elongated, substantially horizontally aligned stabilizer rods 24 which each have one end pivotally connected to the supporting arms 12, and which each have the opposite end thereof extended through a sleeve 26 to a ball joint connection 28 by which the two rods 24 are joined in the center of the rear side 18 of the bulldozer blade 14.

It will be perceived in referring to FIGS. 2 and 3 of the drawings that the stabilizer rods 24 are disposed relatively closely adjacent the lower side or edge of the bulldozer blade 14. It will also be perceived in referring to FIG. 1 that angle braces 29 extend inwardly from a pivotal connection at one of their ends to the supporting arms 12 for pivotal connection at the opposite end to ears 31 carried by the sleeves 26.

In accordance with the present invention, a plurality of scarifier teeth subassemblies 30 are mounted on the rear side 18 of the bulldozer blade 14 adjacent the lower side of the blade, and are horizontally spaced from each other along the blade. Each of the scarifier teeth assemblies 30 includes a mounting bracket subassembly 32. Each mounting bracket subassembly 32 includes a vertically extending anchor plate 34 welded, or otherwise suitably secured, to the backside 18 of the blade 14 and projecting downwardly to the lower side of the blade. At its lower end, the vertically extending plate 34 is secured to a bifurcated horizontally extending anchor plate 36. The forward end of the bifurcated, horizontally extending anchor plate 36 is secured to the under side of a sole anchor plate 38 which is secured to the lower side of the bulldozer blade 14, preferably to a wear plate 40 which is customarily provided at this location.

At its rearward end, the bifurcated, horizontally extending plate 36 has a bifurcation 40 formed therein which receives the shank portion 42 of a scarifier tooth designated generally by reference numeral 44. The scarifier tooth 44 further includes a point 46 attached to the shank portion 42 and angled downward slightly when the shank portion is in a vertically extending position, so as to permit the tooth point 46 to bite into the earth.

The scarifier tooth 44 of the scarifier tooth assembly 30 is mounted in the mounting bracket subassembly 32 by means of a pair of substantially parallel, horizontally extending pivot plates 50 which extend on opposite sides of the shank 42 of the scarifier tooth 44, and which receive a horizontally extending pivot pin 52 passed through these parallel plates and through the upper end portion of the shank 42 of the tooth. It will be noted that the pivot pin 52 is located more closely adjacent the forward edge of the shank'42 than the rear edge thereof, since during loading of the scarifier tooth 44 as it rips into the earth, the force imposed on the forward side of the shank 42 is greater than that acting on the rear side thereof. This will be more clearly apparent as the description of the invention proceeds.

The parallel plates 50 are secured at their lower, longitudinally extending edges to the upper side of the bifurcated, horizontally extending plate 36. The ends of these parallel plates, opposite the ends between which the scarifier tooth 44 is pivotally mounted, are welded to the rearwardly facing side of the vertically extending plate 34. The upper longitudinal edges of the parallel plates 50 are welded to a pair of parallel, substantially horizontally oriented brace plates 54 which also extend on opposite sides of the upper end portion of the shank portion 42 of the scarifier tooth 44.

Although in the illustrated embodiment of the invention, the mounting bracket subassemblies 32 are illustrated as fabricated structures including the several plates described which are secured together by welding or other suitable means, it will be understood that the mounting bracket subassemblies can also be cast as an integral unit.

OPERATION In referring to the location of the scarifier tooth assemblies 30 with respect to the bulldozer blade 14 and the sliding center ball brace assembly 22, it will be noted that the mounting bracket subassemblies 32 are positioned immediately below the stabilizer rods 24 forming a part of the ball brace assembly, and are constructed so that vertical and horizontal force components are transmitted through substantial metallic areas directly to the bulldozer blade. The scarifier teeth 44 are mounted for pivotation about horizontal axes which extend through the respective pivot pins 52. Each tooth can pivot in the manner shown by the dashed and solid line positions of the tooth shown in FIG. 3. When one of the teeth 44 has been pivoted to the vertically extending position shown in solid lines in this figure, it is arrested from further pivotation in a counterclockwise direction (as viewed in FIG. 3) by the abutment of the rear side of its shank 42 against the base of the bifurcation 40 formed in the bifurcated, horizontally extending plate 36. The leverage which transmits the force of the resisting earth to the pivot pin 52 when the blade is in this digging orientation acts so that the force is applied to the relatively thick expanse of metal forming that portion of the shank 42 between the pivot pin and the forward edge ofthe shank which is most nearly adjacent the bulldozer blade.

It will be perceived that the location of the diagonal braces 29 forming a portion of the ball brace assembly 22 effectively prevents the mounting of at least the two most centrally located scarifier tooth assemblies 30 at a position on the rear side 18 of the blade 14 which is above the horizontally extending stabilizer rods 24. Location of the scarifier tooth assemblies 30 in such an elevation on the bulldozer blade 14 would result in the pivoting scarifier teeth 44, during forward movement of the tractor when the bulldozer blade is in use, frac turing, or at least damaging, the diagonal braces 26.

Mounting of the scarifier tooth assemblies in the location shown in the drawings, and by the use of the mounting bracket subassemblies 32, provides a very strong mechanical arrangement which is characterized in having a long and trouble-free service life and which permits effective scarifying and pulverization of the earth to the rear of the bulldozer blade 14 during reverse movements of the tractor 10.

Although a preferred embodiment of the invention has been herein illustrated and described in detail, it will be understood that various changes and modifications to this structure, specifically described here for.

purposes of example, can be effected without departure from, or relinquishment of, the basic principles which underlie the invention. Such modifications and changes which do not depart from these basic principles are therefore deemed to be circumscribed by the spirit and scope of the invention, except as the same may be necessarily limited by the appended claims or reasonable equivalents thereof.

What is claimed is: j

1. Earth working apparatus for mounting on a self propelled vehicle comprising:

an elongated bulldozer blade havinga forward side,

a back side and a substantially horizontally extending lower side;

a sliding center ball brace assembly extending across the back side of the blade in a horizontal direction, said ball brace assembly including a pair of horizontally extending stabilizer rods;

a plurality of horizontally spaced scarifier teeth assemblies mounted on the back side of the blade below the level of said rods and between said ball brace assembly and the lower side of the blade, each of said scarifier teeth assemblies including:

a mounting bracket subassembly secured to the blade adjacent the lower side thereof and including a vertically extending portion flatly abutting the back side of said blade, and a horizontally extending portion flatly abutting the lower side of said blade; and

a scarifier tooth pivotally mounted in said mounting bracket subassembly for pivotation about a horizontal axis from a vertically extending position in a direction away from said blade; and

arm means for pivotally supporting said blade on said vehicle, said arm means including a pair of horizon tally spaced arms, each having one end adapted for pivotal connection to said vehicle, and a second end secured to said blade adjacent an end thereof.

2. Earth working apparatus as defined in claim 1 wherein said sliding center ball brace assembly is further characterized in including joint means interconnecting said horizontally extending stabilizer rods at adjacent ends thereof at a location near the center of said blade;

and wherein the ends of said rods opposite said joint means are connected to said arms.

3. Earth working apparatus as defined in claim 1 wherein said mounting bracket subassembly comprises:

a vertically extending plate secured to the back side of the blade;

a bifurcated, horizontally extending plate secured to the lower end of the vertically extending plate and the lower side of the blade and having the respective scarifier tooth extending through the bifurcation therein; and

a pair of parallel, horizontally spaced pivot plates extending on opposite sides of the respective scarifier tooth associated with the mounting bracket subassembly and secured at their lower edges to said bifurcated plate and at their forward ends to said vertically extending plate; and

a pivot pinextending through said respective scarifier tooth and pivot plates for supporting the tooth for pivotation about a horizontal axis.

4. Earth working apparatus as defined in claim 3 wherein said vertically extending plates of said mounting bracket subassemblies extend upwardly on the back side of said blade between said stabilizer rods and said blade to a level higher than the horizontal planes occupied by said stabilizer rods.

5. Earth working apparatus as defined in claim 3 wherein said stabilizer rods are spaced rearwardly from said blade, and each of said rods is connected at one end to one of said arms; and

wherein said ball brace assembly is further characterized in including joint means interconnecting the ends of said rods opposite their ends connected to said arms, said joint means allowing relative motion between said rods.

6. Earth working apparatus as defined in claim 5 wherein said vertically extending plates are positioned between said rods and said blade.

7. Apparatus for removing earth comprising, in combination:

a tracked, self-propelled vehicle;

an elongated blade positioned forwardly of the vehicle and having a front side, a back side and a lower side;

a pair of horizontally extending stabilizer rods mounted to the back side of the blade and spaced horizontally therefrom, said rods being aligned in end-to-end relation to each other and together extending substantially the entire length of the blade;

a plurality of horizontally spaced mounting bracket subassemblies secured to the back side and lower side of the blade, each of said mounting bracket subassemblies comprising:

a vertical plate secured to the back side of the blade between the blade and one of said stabilizer rods;

a horizontally extending bifurcated plate secured to the lower end of the vertical plate and the lower side of the blade; and

substantially parallel, horizontally extending spaced pivot plates secured to upper side of said bifurcated plate;

a scarifier tooth pivotally mounted in each mounting bracket subassembly between said pivot plates and extending through the bifurcation is said bifurcated plate; and

arms pivotally mounting said blade on said vehicle.

8. Apparatus as defined in claim 7 wherein each of said scarifier teeth includes a point and a shank portion;

and wherein said apparatus further includes pivot pins extending horizontally through said pivot plates of each mounting bracket subassembly and through the shank portion of the scarifier tooth mounted between the respective pivot plates, said pin passing through said shank portion at a location nearer the rear'edge thereof than the forward edge thereof.

9. Earth working apparatus comprising, in combination:

an elongated bulldozer blade having a substantially flat vertically extending back side, and having a generally horizontally extending plate forming a lower side thereof;

a tracked, self-propelled vehicle;

arms pivotally mounting said bulldozer blade on said vehicle;

a pair of horizontally extending stabilizer rods mounted to the back side of the bulldozer blade, spaced horizontally therefrom and extending substantially parallel thereto, said rods being aligned in end-to-end relation to each other, and together extending over a substantial portion of the length of the blade;

plurality of horizontally spaced mounting bracket subassemblies secured to the back side of said blade, each of said mounting bracket subassemblies comprising:

a pair of horizontally extending pivot plates projecting in a horizontal direction from the back side of said blade adjacent the lower side thereof;

a first anchor plate secured to and supporting said pivot plates, and secured to said blade at a location below the level of said stabilizer rods; and

a second anchor plate secured to and supporting said pivot plates, and secured to the vertically extending back side of said bulldozer blade at a location above the level of said stabilizer rods; and

a scarifier tooth pivotally mounted in each mounting bracket subassembly between said pivot plates and located in the respective mounting bracket subassembly at a location such that pivotation of said scarifier tooth does not bring said tooth into contact with said horizontally extending stabilizer rods. 

1. Earth working apparatus for mounting on a self-propelled vehicle comprising: an elongated bulldozer blade having a forward side, a back side and a substantially horizontally extending lower side; a sliding center ball brace assembly extending across the back side of the blade in a horizontal direction, said ball brace assembly including a pair of horizontally extending stabilizer rods; a plurality of horizontally spaced scarifier teeth assemblies mounted on the back side of the blade below the level of said rods and between said ball brace assembly and the lower side of the blade, each of said scarifier teeth assemblies including: a mounting bracket subassembly secured to the blade adjacent the lower side thereof and including a vertically extending portion flatly abutting the back side of said blade, and a horizontally extending portion flatly abutting the lower side of said blade; and a scarifier tooth pivotally mounted in said mounting bracket subassembly for pivotation about a horizontal axis from a vertically extending position in a direction away from said blade; and arm means for pivotally supporting said blade on said vehicle, said arm means including a pair of horizontally spaced arms, each having one end adapted for pivotal connection to said vehicle, and a second end secured to said blade adjacent an end thereof.
 2. Earth working apparatus as defined in claim 1 wherein said sliding center ball brace assembly is further characterized in including joint means interconnecting said horizontally extending stabilizer rods at adjacent ends thereof at a location near the center of said blade; and wherein the ends of said rods opposite said joint means are connected to said arms.
 3. Earth working apparatus as defined in claim 1 wherein said mounting bracket subassembly comprises: a vertically extending plate secured to the back side of the blade; a bifurcated, horizontally extending plate secured to the lower end of the vertically extending plate and the lower side of the blade and having the respective scarifier tooth extending through the bifurcation therein; and a pair of parallel, horizontally spaced pivot plates extending on opposite sides of the respective scarifier tooth associated with the mounting bracket subassembly and secured at their lower edges to said bifurcated plate and at their forward ends to said vertically extending plate; and a pivot pin extending through said respective scarifier tooth and pivot plates for supporting the tooth for pivotation about a horizontal axis.
 4. Earth working apparatus as defined in claim 3 wherein said vertically extending plates of said mounting bracket subassemblies extend upwardly on the back side of said blade between said stabilizer rods and said blade to a level higher than the horizontal planes occupied by said stabilizer rods.
 5. Earth working apparatus as defined in claim 3 wherein said stabilizer rods are spaced rearwardly from said blade, and each of said rods is connected at one end to one of said arms; and wherein said ball brace assembly is further characterized in including joint means interconnecting the ends of said rods opposite their ends connected to said arms, said joint means allowing relativE motion between said rods.
 6. Earth working apparatus as defined in claim 5 wherein said vertically extending plates are positioned between said rods and said blade.
 7. Apparatus for removing earth comprising, in combination: a tracked, self-propelled vehicle; an elongated blade positioned forwardly of the vehicle and having a front side, a back side and a lower side; a pair of horizontally extending stabilizer rods mounted to the back side of the blade and spaced horizontally therefrom, said rods being aligned in end-to-end relation to each other and together extending substantially the entire length of the blade; a plurality of horizontally spaced mounting bracket subassemblies secured to the back side and lower side of the blade, each of said mounting bracket subassemblies comprising: a vertical plate secured to the back side of the blade between the blade and one of said stabilizer rods; a horizontally extending bifurcated plate secured to the lower end of the vertical plate and the lower side of the blade; and substantially parallel, horizontally extending spaced pivot plates secured to upper side of said bifurcated plate; a scarifier tooth pivotally mounted in each mounting bracket subassembly between said pivot plates and extending through the bifurcation is said bifurcated plate; and arms pivotally mounting said blade on said vehicle.
 8. Apparatus as defined in claim 7 wherein each of said scarifier teeth includes a point and a shank portion; and wherein said apparatus further includes pivot pins extending horizontally through said pivot plates of each mounting bracket subassembly and through the shank portion of the scarifier tooth mounted between the respective pivot plates, said pin passing through said shank portion at a location nearer the rear edge thereof than the forward edge thereof.
 9. Earth working apparatus comprising, in combination: an elongated bulldozer blade having a substantially flat vertically extending back side, and having a generally horizontally extending plate forming a lower side thereof; a tracked, self-propelled vehicle; arms pivotally mounting said bulldozer blade on said vehicle; a pair of horizontally extending stabilizer rods mounted to the back side of the bulldozer blade, spaced horizontally therefrom and extending substantially parallel thereto, said rods being aligned in end-to-end relation to each other, and together extending over a substantial portion of the length of the blade; a plurality of horizontally spaced mounting bracket subassemblies secured to the back side of said blade, each of said mounting bracket subassemblies comprising: a pair of horizontally extending pivot plates projecting in a horizontal direction from the back side of said blade adjacent the lower side thereof; a first anchor plate secured to and supporting said pivot plates, and secured to said blade at a location below the level of said stabilizer rods; and a second anchor plate secured to and supporting said pivot plates, and secured to the vertically extending back side of said bulldozer blade at a location above the level of said stabilizer rods; and a scarifier tooth pivotally mounted in each mounting bracket subassembly between said pivot plates and located in the respective mounting bracket subassembly at a location such that pivotation of said scarifier tooth does not bring said tooth into contact with said horizontally extending stabilizer rods. 